1. Field of the Invention
The present invention relates to a circuit arrangement for telecommunication systems, particularly for telephone exchange systems, including DC-DC converters which are respectively connected at their input side to a pole of a DC source over an input inductance and are connected at their output side over an output inductance to one of two input terminals of a user and which respectively conduct a nonpulsating direct current at their input side and at their output side and in which the terminal of the input inductance facing away from the input of the converter and the terminal of the output inductance facing away from the output are connected to one another by way of a storage capacitor. Furthermore, on the basis of a switch arrangement, the storage capacitor is connectible between the input inductance and the other pole at the direct voltage source and the terminal of the output inductance facing away from the output is connected both to the other input terminal of the user, being continuously alternately connectible therewith, and the storage capacitor is switchable between the output inductance and the other input terminal of the user and the terminal of the input inductance facing away from the input of the transducer is connectible to the other pole of the direct voltage source.
2. Description of the Prior Art
A circuit arrangement of the type generally set forth above is already known from the German published application No. 2,842,262, particularly with reference to FIG. 5, which publication is fully incorporated herein by this reference. This arrangement provides that one terminal of a user is connected over the DC-DC converter to the one terminal of the direct voltage source, whereas the other terminal of the user is directly connected to the other terminal of the direct voltage source. For the purpose of a DC-wise potential separation, FIGS. 10ff of the published application provide a transformer which, therefore, is required in addition to the mentioned inductances.